Lithographic Apparatus, Device Manufacturing Methods, Mask and Method of Characterising a Mask and/or Pellicle

摘要

A thick pellicle is allowed to have a non-flat shape and its shape is characterized to calculate corrections to be applied in exposures to compensate for the optical effects of the pellicle. The pellicle may be mounted so as to adopt a one-dimensional shape under the influence of gravity to make the compensation easier.